This section provides background information related to the present disclosure which is not necessarily prior art.
Known systems used to control operations of metal processing baths such as for aluminum processing can include pneumatic valves and piping used to drive a crust breaking tool to create an aperture by breaking through the hardened upper crust layer formed on the bath. The crust breaking tool is intended to open the aperture to permit addition of additional alumina material to the molten bath of aluminum. When creation of the aperture has been confirmed, pressurized air directs the crust breaking tool to retract from the crust layer. The drawbacks of such systems include the large volumes of pressurized air which are used to control a normal crust breaking operation, and particularly when crust material forms on the crust breaking tool such that bath detection cannot occur, and/or when the crust breaking tool cannot penetrate the crust layer.
In these situations, the crust breaking tool can remain in the bath for an undesirable length of time which can damage the crust breaking tool, or render the detection system inoperative. Also in these situations, the subsequent feeding of new alumina material into the bath can be hindered, or the system may be unable to identify how many feed events have occurred, thus leading to out-of-range conditions in the bath. A further drawback of known control systems is the large volume of high pressure air required significantly increases operating costs of the system due to the size and volume of high pressure air system requirements, power consumption and cost, the operating time of pumps/compressors, and the number of air compressors and air dryers required for operation.